In the spinal cord, white matter is

Options

A. Surrounded by gray matter
B. Mixed with gray matter
C. Around the gray matter
D. Absent

Answer

To answer the question "In the spinal cord, white matter is...", we will analyze the structure of the spinal cord and the arrangement of white and gray matter.

### Step-by-Step Solution:

1. **Understanding the Structure of the Spinal Cord**:
- The spinal cord is a crucial part of the central nervous system (CNS) and is encased within the vertebral column. It extends from the base of the brain (specifically from the foramen magnum of the medulla oblongata) down to the lumbar region of the spine.

2. **Identifying White and Gray Matter**:
- The spinal cord consists of two types of nervous tissue: white matter and gray matter.
- White matter primarily contains myelinated axons, which are responsible for the transmission of signals between different parts of the nervous system.
- Gray matter consists mainly of neuronal cell bodies, dendrites, and unmyelinated axons.

3. **Arrangement of White and Gray Matter**:
- In the spinal cord, the arrangement of white and gray matter is different from that in the brain.
- In the spinal cord, the white matter is located on the outside, surrounding the gray matter, which is found in the center of the spinal cord.
- This is in contrast to the brain, where gray matter is located on the outside (cortex) and white matter is found beneath it.

4. **Conclusion**:
- Therefore, in the spinal cord, white matter is **surrounding the gray matter**.

### Final Answer:
In the spinal cord, white matter is surrounding the gray matter.

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